Fan shroud



is. P. LAMB Feb. 9, 1954 FAN SHROUD 2 Sheets-Sheet 1 Filed Dec. 11, 1952 INVENTOR. X4 771 [fr/es? E. P. LAMB FAN SHROUD 2 Sheets-sheaf. 2

Filed Dec. 11, 1952 Z R m4 2 N la M e 3 4. T; a w 0 MW 0 Q 6 w Q Q Q FKNT SHROUD Uhnyslefi Gorpoi-ation, Highland corporation of Delaware "lab;- i'osse whitewash-Mich tasark,

""Thisunvemicn 're'lates 'to a fa'n shroudaud more particularlya"mouiitiiig for' the shroud which-"facilitates"positioning" the"shroud "inflextrem'ely "close relationship tothe fan-bladetips.

*It "has lreretofore'been common practiceto 'mount an engineanda radiator-one supporting structure'- with "the engine resiliently ="-mounted thereonarid "thefrad'iator' rigidly mounted there- 'on. In autombbiles' and industrial "powe'ruuiits 'WhereWhiS rriouiiting"is" commonly used there is" generally" provided afmulti-bl'aded i an which ispoSitioned -between""the"engine and radiator and'driven 'by theeiigi'rre. The fan is intended to'draw air throughfthe radiator to coola liquid which is 'circulated'throtigh the radiator and engme-t -contro1 the temperature of the r engine.

In the above cofi struction it is ev'i'dentthat as the engine rocks and moves on its resilient mountings the fan also moves relative to the radiator. sinceit' -h'as 'been conimon practice to provide a metal shroud to define an air path from the radiator to the fan and to mount this shroud on the radiator the relative movement between the fan and shroud necessitates that the shroud be of considerably larger diameter than the fan so that there will be no interference between the fan blade tips and the shroud and this detracts from the efiectiveness of the shroud in controlling air flow.

It is a principal object of this invention to provide a shroud which has a rigid portion of ring-like configuration circumscribing the fan in close proximity to the fan blade tips and supported by the engine for movement therewith and that this rigid portion of the shroud be connected to the radiator by a flexible or bellowslike portion.

By providing a shroud that has a minimum space between it and the fan blade tips the air flow through the radiator for any given size of fan is increased and this makes it possible for savings to be obtained by reducing the size of the radiator or the fan.

In the drawings:

Fig. 1 is a side elevation of a portion of an engine, it support and associated radiator and fan provided with my invention;

Fig. 2 is a vertical section on the line 22 of Fig. 1; and

Fig. 3 is a vertical section on the line 3-3 of Fig. 1.

A frame l0 having a side rail I2, and cross members I4 and I6 is provided as a support. An air cooled radiator I8 is bolted to a radiator emaims. (Cl. 123 41J49) 5. An engine 2a is 'supported byithe' raineron resilient mouritin'gs, one -off which is- 'illus'trated and then thr'ough'the i a'diator for oling. I

A -"multi bla'dedfan 3 having ulleyi-wheel 36 connected therto' is rotatably "ountedon the water pump 32 of engine w 'and to be driven byf af -belt 38. The :belt ay ibe driven a @conventionawmanner, avhich has has been ill-ustra-ted a'lthoiigh it is coinmonipractice to -'-provide a: pulley wheel* on the" engine crankshaft. for purpose. 7

shroudflni is 'provideri to diretiiair passing through the intermediate core structure 28 to the fan 34 to increase the flow of air over the core structure. The shroud 40 includes a rigid portion 42 of ring like configuration, which is preferably assembled from upper and lower halves secured together by bolts 44. The rigid portion 42 is retained in concentric relation with respect to fan 34 by a plurality of braces 46 secured to the engine 20. Since the fan 34 and rigid portion 42 of shroud 49' are both carried by the engine they will move together when the engine 20 moves on its resilient mountings 22 and, therefore, the clearance between the fan blade tips and the rigid portion 42 of the shroud 40 may .be very small.

The shroud 40 also includes a flexible portion 48 which is connected to the ring-like portion 42 by screws 50 and is connected to the radiator support I9 around the periphery of the core structure by screws 5|. The flexible portion 48 is provided with a round opening at one end adjacent the rigid portion 42 and a rectangular opening at the other end adjacent the radiator core structure 28.

During operation the rigid portion 42 of shroud 40 and the fan 34 will move with the engine relative to the frame [0 when the engine moves on its resilient mountings and the radiator will not move relative to the frame III. The flexible portion 48 of shroud 4'0 whichis secured between the rigid shroud portion 42 and the radiator support I9 will accommodate the relative movement involved.

I claim:

1. A power unit including an internal combustion engine rockably movable as an incident to its operation, a fan driven by the engine and movable therewith, a stationary heat exchanger unit in fluid flow communication with the engine and a shroud for the fan comprising a ring element mounted on said engine in concentric relation to said fan and a flexible casing defining an air passage and having one end secured to said ring element and the other end secured to said radiator.

2. A power unit including a supporting structure, an internal combustion engine resiliently mounted thereon, an air cooled radiator rigidly mounted on said supporting structure, a fan driven by the engine and carried therewith, said fan being located between said engine and said radiator, and a shroud comprising a rigid portion circumscribing said fan and mounted on said engine and a flexible portion extending between said rigid portion and said radiator.

3. A power unit including an internal combustion engine and an air cooled heat exchanger, said engine and said heat exchanger being mounted for limited relative movement, a fan driven by the engine and supported thereby, said fan being located between said engine and said heat exchanger, and a shroud comprising a rigid portion of ringlike configuration supported by said en- .gine in concentric relation with said fan an a flexible portion carried by said rigid portion and said heat exchanger and defining an air path from said heat exchanger to said rigid portion.

4. A power unit including an internal combustion engine and an air cooled heat exchanger, said engine and said heat exchanger being mounted for limited relative movement, a fan driven by the engine and supported thereby, said fan being located between said engine and said heat exchanger, and a shroud comprising a, rigid portion of ring-lik configuration supported in concentric relation with said fan by spaced brackets secured to said engine, said brackets being suificiently small to present a, minimum obstruction to the passage of air through said shroud and a flexible portion carried by said rigid portion and said heat exchanger and defining an air path from said heat exchanger to said rigid portion.

5. A power unit including an internal combustion engine and an air cooled heat exchanger, said engine and said heat exchanger being mounted for limited relative movement, a fan driven by the engine and supported thereby, said fan being located between said engine and said heat exchanger, and a shroud comprising a rigid portion of ringlike configuration supported by said engine in concentric relation with said fan and a flexible portion carried by said rigid portion and said heat exchanger and defining an air path from said heat exchanger to said rigid portion, said flexible portion having a bellows-like configuration to accommodate relative movement between said rigid portion and said heat exchanger.

6. A power unit including an internal combustion engine and an air cooled heat exchanger, said engine and said heat'exchanger being mounted for limited relative movement, a bladed fan driven by the engine and supported thereby, said fan being located between said engine and said heat exchanger, and a shroud comprising a rigid portion of ring-like configuration having a cross section approximating the curvature of the fan blade tips, said rigid portion being supported by said engine with a very small radial clearance between the fan blade tips and said rigid portion, and said shroud further comprising a flexible portion carried by said rigid portion and said heat exchanger and defining an air path from said heat exchanger to said rigid portion.

ERNEST P. LAMB.

No references cited. 

